pOptical Earth observation satellites provide vast amounts of data on a daily basis. The top-of-atmosphere radiance measured by these satellites is usually converted to bottom-of-atmosphere radiance or reflectance which is then used for deriving numerous higher level products used for monitoring environmental conditions, climate change, stock of natural resources, etc. The increase of available remote sensing data impacts decision-making on both regional and global scales, and demands appropriate quality control and validation procedures. A HYperspectral Pointable System for Terrestrial and Aquatic Radiometry (HYPSTAR$^®$) has been designed to provide automated, italicin-situ/italic multiangular reflectance measurements of land and water targets. HYPSTAR-SR covers 380–1020 nm spectral range at 3 nm spectral resolution and is used at water sites. For land sites the HYPSTAR-XR variant is used with the spectral range extended to 1680 nm at 10 nm spectral resolution. The spectroradiometer has multiplexed radiance and irradiance entrances, an internal mechanical shutter, and an integrated imaging camera for capturing snapshots of the targets. The spectroradiometer is mounted on a two-axis pointing system with 360° range of free movement in both axes. The system also incorporates a stable light emitting diode as a light source, used for monitoring the stability of the radiometric calibration during the long-term unattended field deployment. Autonomous operation is managed by a host system which handles data acquisition, storage, and transmission to a central WATERHYPERNET or LANDHYPERNET server according to a pre-programmed schedule. The system is remotely accessible over the internet for configuration changes and software updates. The HYPSTAR systems have been deployed at 10 water and 11 land sites for different periods ranging from a few days to a few years. The data are automatically processed at the central servers by the HYPERNETS processor and the derived radiance, irradiance, and reflectance products with associated measurement uncertainties are distributed at the WATERHYPERNET and LANDHYPERNET data portals./p
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RBINS Staff Publications 2025
New global standards on sulphur content in marine fuels have led to an increasing number of ships installing exhaust gas cleaning systems, also known as scrubbers, to reduce air emissions of sulphur oxides. Ships equipped with a scrubber can continue to use heavy fuel oil, resulting in significant discharge of acidified water containing several contaminants, such as heavy metals, persistent organic pollutants (POPs; mainly polycyclic aromatic hydrocarbons), and nitrogen compounds.The simplest and most common type of scrubber system, the open-loop scrubber, directly discharges the contaminated water in to the sea. The use of scrubber systems by ships is an emerging global problem and an additional pressure on the marine environment. The substances found in scrubber discharge water can cause acute effects on marine biota and may have further impacts, through bioaccumulation, acidification, and eutrophication, on the structure and functioning of marine ecosystems.The number of ships with installed scrubber systems is increasing, but legislation on scrubber discharge is lagging, inconsistent between countries, and often insufficient to protect the environment. ICES recommends the use of cleaner low-sulphur fuels, such as marine gas oil, to eliminate scrubber use and associated impacts on the marine environment.Until this is possible, ICES proposes a set of measures to mitigate scrubber impacts
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RBINS Staff Publications 2020
